Hi,
That’s exactly what I had in my 1966 E-type 2+2 automatic to MOD conversion, best of both worlds! Of course it’s a bit lighter car than a MKX but anyways.
And I can not speak for manual MKX’s but on the E-types the factory did use a different center tunnel as the automatic gearbox was much bigger & wider than the manual gearbox. As a result there was so much extra room in my ex 2+2 that I could change the gearbox oil from underneath the car with a hose and a hand pump.
Cheers!